Brush-holder.



R. G. CLARK.

BRUSH HOLDER. APPLICATION FILED MAR. 6. 1916.

Patentxad May 15, 1917.

@ Will UNITED STATES PATENT OFFICE.

ROBERT G. CLARK, OF NEW YORK, N. Y.

BRUSILHOLDER.

Application filed March 6, 1916.

i for electric machinery, such as motors and generators, the object being to provide a simpleform of adjustment by means of which the pressure of the brush against the commutator of the electric machine may be regulated.

In carrying out the invention I provide a brush holder of suitable form and adjustable resilient means operating against the brush. The principal feature of this invention is in the said adjustable resilient means'and will be pointed out more fully hereinafter in connection with the description of the device shown in the accompanying drawings illustrating one embodiment of the invention. v

In the drawing like parts in the several views have been given the same reference numerals.

Figure 1 is a plan view of a brush holder, embodying the invention.

Fig. 2 is a side elevation of Fig. 1.

Fig. 3 is a sectional view of a part of the device, taken on the line 33 of Fig. 1.

Fig. 4 is a detailed view of one of the elements of the device.

Fig. 5 is a detailed view similar to Fig. 4:, showing a modification of the same.

A brush holder frame is shown at 1 and may be of any suitable or desired construction to receive the brush 2. The holder as shown in the drawings is adapted to carry two separate brushes, but it will be understood that the same may be constructed to hold any number of brushes as may be required. The brush 2 is slidably mounted or loosely held in the frame 1 and is pressed against the commutator of the machine, not shown in the drawings, by means of a spring member 3. The spring member 3 may have a contact member 4 attached thereto near one end and provided with a curved contact surface bearing against the brush 2, as shown in Fig. 2. The spring member 3 at its opposite end is shaped in the form of a spiral with its inner end bent inwardly and engaged in a slot in a supporting member 5.

Specification of Letters Patent.

Patented May 15, 1917.

Serial No. 82,319.

The supporting member 5 is preferably in the form of a pin or rod rotatively mounted in projecting arms from one side of the frame 1 and is provided at its outer end with one or more transverse openings 6 into which a small rod may be inserted for turning the supporting member 5 to place a tension upon the spring 3 by winding the spiral portion thereof around the supporting member 5 until a suflicient tension has been produced to cause the outer end of the spring 3 to bear downwardly on the brush 2 with sufficient force to hold the same against the commutator with the desired pressure.

The supporting member 5 is provided with an annular recess 7 which in turn may be provided with a number of recesses, as shown in Fig. 4, or may be provided with a knurled surface, as shown in Fig. 5.

As shown in Fig. 3, an opening 8 is provided in one of the extending arms of the frame 1 in a position so that when the supporting member 5 is in position in the frame the annular recess 7 will be positioned opposite the opening 8. A small steel ball 9 is placed in the opening 8 and rests upon a small spiral spring 10 in the lower portion of said opening. This spring 10 holds the ball 9 in engagement with the supporting member 5, either in one of the recesses in understood and it will be seen that the con-- struction permits the turning of the supporting member 5 in a counter-clockwise direetion to wind up or increase the tension of the spring member 3 and when the supporting member 5 tends to turn. in the opposite direction, the engagement of the ball 9 in the annular recess 7 will hold the same against turning and so maintain the spring member 3 under tension.

When it is desired to release the supporting member 5, to allow the spring to unwind or decrease the tension, it is only necessary to insert a small rod in the opening 8 and force the ball 9 downwardly out of engagement with the supporting member 5, when the same may be freely turned until the ball 9 is released. The lower portion of the opening 8 may be somewhat smaller in diameter than the upper portion and provides a shoulder 15 to limit the downward movement of the ball 9 and so prevent the spring 10 from being unduly compressed.

The engagement of the ball 9 in the recess 7 also holds the supporting member 5 in position in the frame 1 and prevents the same from being accidentally forced outwardly or from dropping out while, at the same time, permits the same being rotated as above described. When it is desired to remove the support 5 from the frame 1 it is only necessary to insert the rod in the hole 8 and force the ball 9 downwardly against the shoulder, when the supporting member 5 may be easily Withdrawn.

It will thus be seen that an adjustment is provided which is suitable in construction, efiicient and automatic in operation and which may be easily and cheaply manufactured.

What I claim is:

1. In a brush holder, in combination, a brush holder frame adapted to hold a brush, a spring member adapted to operatively engage said brush, a supporting member upon which said spring member is mounted, said supporting member being rotatively mounted in said frame, and a locking device normally in position to lock said supporting member against rotation in one direction and to permit free rotation of said supporting member in an opposite direction, said locking device comprising a ball positioned in an opening in said frame and adapted to engagesaid supporting member.

2. In a brush holder, in combination, a brush holder frame adapted to hold a brush, a spring member adapted to operatively engage .said brush, a supporting member upon which said spring member is mounted, said supporting member being provided with an annular recess having a roughened surface,

and a spring pressed ball positioned in an opening in the frame and adapted to engage in said annular recess to lock the said sup porting member against rotation in one direction only.

3. In a brush holder, in combination, a brush holder frame adapted to hold a brush, a spring member adapted to operatively engage said brush, a supporting member upon which said spring member is mounted, said supporting member being rotatively mounted in said frame, and means comprising a ball positioned in an opening in said frame and normally engaging said supporting member in a manner to permit rotation thereof in one direction and to prevent rotation thereof in the opposite direction to adjustably maintain said spring member under tension, said opening being provided with a shoulder to limit the movement of said ball.

4. In a brush holder, in combination, a brush holder frame adapted to hold a brush, a spring member adapted to operatively engage said brush, a supporting member upon which said spring member is mounted, said supporting member being rotatively mounted in said frame, and means comprising a ball and a spring positioned in an opening in said frame, said spring and ball being adapted and arranged so that said ball is caused to engage said supporting member and to permit rotation thereof in one direction but prevent rotation in the opposite direction whereby said spring member is adjustably maintained under tension.

Signed at the city, county and State of New York, this 2d day of March, 1916.

ROBERT G. CLARK.

copies of this patent may be obtained for five cents each, by nddrenlng the Gommiuloner of Patente, Washington, D. 0." 

